1. Field of the Invention
The present invention relates to an automatically closing hinge and an electronic device using the hinge, and more particularly to a hinge using an inclined-surface slider mechanism and a torque limiter to achieve the automatically closing function and to allow the components attached to the hinge to remain stationary, and an electronic device using the hinge.
2. Related Art
Hinges are common mechanical components used in electronic devices, such as mobile phones, flatbed scanners, office machines, and etc. Two hinges can connect a base to a cover of the electronic device. In the scanner, for example, the user can open the cover, place a document and close the cover to press the document, so that the document can be scanned. More particularly, when the cover of the scanner is equipped with a sheet-feeding mechanism, the overall weight of the cover is increased due to the presence of the sheet-feeding mechanism. In order to prevent the cover from suddenly closing up by its own weight, the used hinges are usually configured to open up and remain stationary at a predefined angle, such that the user can conveniently place the document on the platen. This type of hinge usually contains multiple sets of friction plates in conjunction with a spring providing a lateral force to fix the angle of the cover by way of friction. In another type of hinge, a torsion spring is utilized and the torque of the torsion spring is restricted to achieve the object of fixing the hinge at the predefined angle. However, these hinges encounter the problem that the friction plates need to be manufactured by steel sheets, and the cost is increased. In addition, the friction caused by utilizing the spring to exert the force to the friction plate cannot be adjusted easily and neither can be controlled, due to the attenuation of the elasticity of the spring.
In addition, the hinge is also configured to automatically close the cover when an angle is reached in order to avoid problems arising out of the cover not properly closed. This hinge with the automatically closing function is typically based on the property of interference deformation of a plastic member. When the cover is pushed downward to a position of a predefined angle, the energy of the deformed plastic member is released to provide a downward force and to automatically close the cover. In such a hinge, the angle at which the cover is automatically closed cannot be easily and precisely controlled, and the lifetime of the plastic member is shortened because the plastic member is continuously in the deformed state.